Ok no offence intended here but based on your picture and the level of complexity i would guess you are a GCSE student, so i will try and remember how they teach it at GCSE

Well Nitrogen has 7 electrons. So that means 2 in the first shell, and 5 in the 2nd shell. That means that the electron from each hydrogen covalently bonds with one electron in the 2nd shell of nitrogen, and then the 2 extra electrons in nitrogen exist as a lone pair.

This gives a 2nd shell in nitrogen with 8 electrons, like it wants.
and each hydrogen has 2 electons in the first shell, which they want

yeap, the bohr model of the atom is inaccurate. what u're learning now probably revolves around 1st shell having 2 electrons, and the rest having 8 each. just a header: the sun/planet model of an atom (the one normally shown to represent nuclear related physics) is wrong too.

What do you do when the last day of your life is approaching...........?
Me?
I still go about living life the way I always have.

well organic products typically exist in nature, for example the protiens in your body are long chains of amino acids, (like histadine)..btw i'm not a biologist so if i just said something totally wrong please correct me

To find the number of electrons used in covalent bonding, you need to look at the valence shell only. Although nitrogen has 7 electrons total as a neutral atom, the first two are in its first energy level and are thereby not part of the outer shell that is involved in bonding.If you follow your finger across the periodic table for the energy level that nitrogen is on (aka period 2), there are 2 valence electrons in its s orbital for that energy level, and 3 in the p orbital. Although nitrogen has 7 electrons total as a neutral atom, the first two are in its first energy level and are thereby not part of the outer shell that is involved in bonding.

Since nitrogen has 5 valence electrons, two of the electrons pair, leaving three to bond with other atoms. This allows three hydrogen atoms, which each have 1 valence electron, to pair their electron with nitrogen's. (AMMONIA)

When the covalently bonded AMMONIUM ion forms, one of the valence electrons that would normally be paired is excluded, and another hydrogen is allowed to pair with the lone electron. So you have NH4, and it will have an overall charge of +1, reflecting the excluded electron.

**This all makes more sense if you draw the Lewis dot structure and look at it...